Gun violence in the United States is a serious public health concern. The nation's firearm death rate is the highest among industrialized nations, with an alarmingly high rate among African-American youth. We will examine childhood and adolescent contextual and individual predictors of late adolescent and early adulthood gun attitudes and gun violence among a sample of urban, mostly African-American youth, as well as factors that protect these youth from the effects of exposure to violence. First, we plan to follow up a sample of youth in Flint, Michigan, who were in grades 2, 4, and 9 when first interviewed in 2006-07. We have extensive 3-year prospective data on their media exposure, exposure to violence in the neighborhood and family, parenting, social cognitions related to aggression, and academic and behavioral outcomes (including self, parent, and teacher reports). We will collect geocoded crime data on their neighborhoods while growing up (e.g., exposure to gun violence and related gun crimes, independent of other forms of violence exposure, using geospatial analytic methods), and re-interview the participants again (ages 18, 20, and 25 years of age) on their attitudes toward and use of firearms (and collect criminal data on them). Second, we will conduct a new 3-wave prospective study of high school 10th graders at two sites (Flint, MI and Jersey City, NJ) to expand our knowledge of the risk factors that promote youth's and young adults' violent behaviors with firearms and other weapons; most important, we will collect self-report data on specific social cognitions related to weapon carrying and weapon use, as these weapon-related social cognitions were not available in our earlier study. In both studies, we also will examine potential protective factors (e.g., parenting, constructive social activities, civic engagement) that moderate the effects of exposure to violence on subsequent violent behavior. Our specific aims are to: 1) evaluate the impact of exposure to people's use of weapons (guns, etc.) on risk for violent behavior, including weapon-carrying, weapon use, threatening others with a weapon, and committing crimes with a weapon; 2) examine the role of social cognitions and emotional reactions concerning general aggression and aggression with weapons in mediating the longitudinal effect of exposure to weapon violence on violent behavior; 3) examine the role of individual and contextual factors in moderating the impact of violence exposure on violent behavior; and 4) assess the impact of exposure to weapon violence and general violence at different ages on risk for subsequent weapon carrying and weapon use at later ages. This will allow us to test key theoretical propositions concerning mediating cognitive and emotional processes that might account for the long-term effects of general and weapon-specific violence exposure, as well as protective factors that can inform the development of multi-layered community intervention efforts to reduce gun violence among urban youth.